Albert s



A. S. ANDERSON. EQUALIZER FOR HIOISTS. APPLlCATlON FILED JULY 1,1918.

1,337, 1 1 1. Patented Apr- 13, 1920.

flvenfior:

' art 5 jdmm UNITED STATES PATENT OFFICE.

ALBERT S. ANDERSON, OF ST. PAUL, HINNESOTA, ASSIGNOR T0 GRANT WALDBEF,0F ST. PAUL, MINNESOTA.

EQUALIZEB FOR HOISTS.

Specification of Letters Patent.

Patented Apr.13, 1920.

Application filed July 1, 1918. Serial No. 242,806.

To all whom it may concern:

Be it known that I, ALBERT S. ANDnRsoN, a citizen of the United States,residing at St. Paul, in the county of Ramsey and State of Minnesota,have invented a new and useful Improvement in Equalizers for Hoists, ofwhich the following is a specificatlon.

This invention relates to improvements 1n equalizers for hoists, theprimary object being to provide improved means for equal zing any uneventendency between the hoist and the load which it is adapted to ralse andlower.

In the accompanying drawing form ng part of this specification, Figure 1is a side elevation of a hoist shown applied to a portion of a truckhavin the usual type of dumping body, which is arranged to swing up anddown and showing my improved equalizer; Fig. 2 is a side elevation of.the equalizer arm shown attached to the upper end of the piston rod;Fig. 3 is a plan of the structure illustrated in Fig. 2, and Flg. 4 is aside elevation partly in sectlon of an alternative construction.

My invention is particularly applicable for use in connection with ahoist having the usual hydraulic cylinder 10 mounted upon the frame 11of a truck, said truck having the usual dumping body 12, which isarranged to swing up from said frame of the vehicle at its forward end.The cylinder 10 contains the usual piston 14, which may be of ansuitable construction and adapted to reciprocate up and down, saldpiston having a piston rod 15' projecting through the upper end of thecylinder and having my improved equalizer arm A plyotally mountedbetween the ends of sald arm on the upper end of said piston rod bymeans of the pivot pin 16. This equalizer arm takes the' placeof therigid cross bar formerly used at the upper end of the piston rod and ofthe equalizer used at the bottom'of the hoist fastened to the baseplate. The equalizer arm carries a pair of sheave pulleys 17 and 18 atits opposite ends which in turn carry the cables 19 which l1ft the body.Each sheave pulley is 'ournaled in a sheave housing 20 and each s eavehousing carries an upwardly pro'ecting stud bolt 21 which is securedthroug a half ball bearing 22 which is seated in a cup block Theequalizer arm comprises a air of side plates 24 and 25 secured toget erin para1lel spaced relation at their ends with the bearing cup blocks 23clamped between the side members and serving as spacing blocks byuneansof bolts 26, thus producing a rlgid, strong, inexpensive structure,leavmg an intervening space in which the upper end of the piston rod 15is secured on the pivot pin 16. The cup blocks 23 may thus be easilycase hardened to reduce wear and produce an eflicient bearing for thehalfballs 22 through which the sheave support ng bolts 21 are fastened.The lower portion of the bearing cup block 23 is provlded wlth a passage24 through which the bolt 21 is free to swing and turn, thus allowingthe sheave which is supported to move and evenly distribute andcompensate the load on the piston rod. ()ne end of each of the cables 19is anchored by the bolt 25 to the base member 26 on the frame 11 and theopposite end is connected to the hanger 27, which is fastened to thebody 12, so that as the piston 14 is forced upwardly the body 12 israised into tilting position. Thus the ball and socket jointscooperating with the equalizer arm pivoted between its ends on thepiston rod give perfect alinement of the sheaves and cables whichobviously is an advantage when lifting heavy loads.

The equalizer arm may be variously modified within the spirit of myinvention so long as the ball and socket joints are emplo ed foraccomplishing the results stated. In ig. 4 one modification isillustrated in which said equalizer arm is formed out of a single pieceof material of inverted 'U shape and cross section between its ends andjournaled between its-sides by the pin- 30 over the upper end of thepiston rod 31. The extremities of said equalizer arm are formed withcups 32 in each of which a half ball 33 is seated. The sheave housing 34as in the preferred construction has its hanger bolt 35 secured throughthe half ball, a passage 36 being provided as in the preferredconstruction in the lower portion of the cup through which the hangerbolt is free to swing andturn to compensate for any uneven tendenc naccordance wit the patent statutes, I have described the principles ofoperation of my invention, together with the apparatus which I nowconsider to represent the best embodiment thereof, but I' desire to haveit understood that the construction claim.

Having described my invention, what I,

claim as new and desire to protect by'Let ters Patent is: a

An equalizer, comprising, in combination,

an arm having two sides, pivotally supportedbetween its ends, blocksbetweenthe sides at the opposite ends of said arm, said blocks havingbearing cups in their upper surfaces and ball members seated in andhanging from said cups.

n testimony whereof, I have signed my name to this specification.

- ALBERT S. ANDERSON.

